So every once in awhile I get somebody asking about what actually happens when you click
the red close button to close a window in an application on the Mac.
The confusion comes from the fact that sometimes this seems to quit the app and sometimes it
doesn't quit the app.
So, for instance, here I am in Safari and if I click the red button I can see Safari
is still the app that's running.
I can create a new window in Safari.
I'm still looking at Safari menu items here at the top.
I'm still in Safari.
But then other apps don't act this way.
Here's the Contacts app.
You can see I'm running Contacts.
Here's the Contacts window.
If I click the red button here Contacts actually closes.
The entire application quits.
Why is there a difference between how some apps act when you click the red button and
other apps?
So there is kind of a logic that apps play by when determining what happens when you
click that red button.
It has to do with, what I call, single window apps.
Whether or not an app really consists of a single window or whether there are multiple
windows containing multiple documents used by the app.
So, for instance, Contacts is a single window app.
There's one window here that shows you your contacts and you can go and click on different
ones and it displays the contact to the right.
It's a single window.
When you click the red button you close that single window so it quits.
Other apps have multiple windows usually because you can have multiple Docks open.
For instance the easiest way to demonstrate this is an app that undoubtedly shows you
one window per document.
Here's Pages and we create a window that has this one document in it.
If I create a new document it's in a second window.
I have two windows right now running in Pages.
Now you would imagine that when you click the red button you don't want Pages to quit
because you have another document open.
You may have three or four documents open.
You certainly don't want the entire app to Quit just because you closed one window or
one document.
So it goes to follow that they should be consistent and even when there's one window left when
you close that one window the app stays open.
After all you may be closing that document in order to simply go ahead and open another
one.
So the app doesn't quit.
You have to go to the Menu and Quit or use Command Q to actually quit the app.
So we can look at other apps and see how they work.
For instance, Notes seems to be a single window app.
Sure enough if I click the red button there Notes quits.
Now if we go to something like TextEdit that has multiple windows.
There's a document.
There's another document.
Of course whichever one of those I close it's not going to quit the app.
I close the last one and it still doesn't close the app.
I actually have to Quit it by itself.
Then there are apps that kind of fall in-between.
Sometimes you can rationalize why they don't work this way.
So you have iTunes.
iTunes seems to be a single window app.
After all there is no way for me to open up a second main iTunes window.
But if I click the red button it doesn't quit.
Well, this kind of makes sense because first of all there are two windows that you can
have.
That you can switch between.
So I could go to Window and open the iTunes window or I can switch to MiniPlayer and bring
that up.
That's a second window and if I close this first window the MiniPlayer stays open.
If I close the MiniPlayer it actually automatically opens the main window.
So it's kind of a little bit beyond a single window app.
Plus the fact that of course if I'm playing music in iTunes and I want to close the window
to get it out of the way I don't want iTunes to quit because the music will stop playing.
So it makes sense in that case.
There are some definite exceptions though.
In Calendar you've got what looks like a single window app but if you click the red button
it doesn't quit Calendar.
I can go to Window, Calendar.
Now you can rationalize this a little bit because there is something called the Availability
Panel.
You bring that up and that's a kind of useful thing all on its own.
So closing the main Calendar window to have your Availability Panel open it does kind
of make sense.
It might be the reasoning why Calendar doesn't behave like a single window app.
Of course Safari is an app where you definitely, very often, have more than one window open.
So even though these technically aren't documents, they're webpages, they're like documents.
So you close one window, close another window, you're still in Safari.
It's very likely when you close a window in Safari that you may decide you want to open
another one right away.
You don't want to Quit the app and have to go and restart it.
Whereas in some of these apps, like in Contacts, you're not going to go and say well I want
to go and view another contact.
Let me close this window just to go back to the same window.
If you think of it in terms of that rule then it actually makes sense.
So that's why Contacts quits like that.
There are other apps too.
News is like that as well.
There's a single window for News.
If I click to close that then News Quits because it wouldn't make sense to close the News window
only to reopen it again to go to another location.
So various apps do various different things.
For the most part there's some logic behind it.
It seems like in all cases when an app can deal with multiple windows and multiple documents
clicking the red button will not Quit the app.
It seems like in most cases when it looks like it's a one window app clicking the red
button will Quit the app.
There are a few exceptions and these exceptions kind of can be rationalize a little bit to
make sense.
So I hope that explains it.
It really doesn't change much about how you use your Mac.
But it's interesting to look at.